/*********************************************************************
 * Copyright (C) 2002 Andrew Khan
 * <p>
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * <p>
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * <p>
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 ***************************************************************************/

package jxl.write.biff;

import jxl.WorkbookSettings;
import jxl.biff.ByteData;
import jxl.common.Logger;

import java.io.IOException;
import java.io.OutputStream;

/**
 * A file of excel data to be written out.  All the excel data is held
 * in memory, and when the close method is called a CompoundFile object
 * is used to write the Biff oriented excel data in the CompoundFile
 * format
 */
public final class File {
    /**
     * The logger
     */
    private static Logger logger = Logger.getLogger(File.class);

    /**
     * The data from the excel 97 file
     */
    private ExcelDataOutput data;
    /**
     * The current position within the file
     */
    private int pos;
    /**
     * The output stream
     */
    private OutputStream outputStream;
    /**
     * The initial file size
     */
    private int initialFileSize;
    /**
     * The amount to increase the growable array by
     */
    private int arrayGrowSize;
    /**
     * The workbook settings
     */
    private WorkbookSettings workbookSettings;
    /**
     * The read compound file.  This will only be non-null if there are macros
     * or other property sets of that ilk which that we should be copying
     */
    jxl.read.biff.CompoundFile readCompoundFile;

    /**
     * Constructor
     *
     * @param os the output stream
     * @param ws the configuration settings for this workbook
     * @param rcf the rea compound file
     */
    File(OutputStream os, WorkbookSettings ws, jxl.read.biff.CompoundFile rcf)
            throws IOException {
        outputStream = os;
        workbookSettings = ws;
        readCompoundFile = rcf;
        createDataOutput();
    }

    private void createDataOutput() throws IOException {
        if (workbookSettings.getUseTemporaryFileDuringWrite()) {
            data = new FileDataOutput
                    (workbookSettings.getTemporaryFileDuringWriteDirectory());
        } else {
            initialFileSize = workbookSettings.getInitialFileSize();
            arrayGrowSize = workbookSettings.getArrayGrowSize();

            data = new MemoryDataOutput(initialFileSize, arrayGrowSize);
        }
    }

    /**
     * Closes the file.  In fact, this writes out all the excel data
     * to disk using a CompoundFile object, and then frees up all the memory
     * allocated to the workbook
     *
     * @exception IOException
     * @param cs TRUE if this should close the stream, FALSE if the application
     * closes it
     */
    void close(boolean cs) throws IOException, JxlWriteException {
        CompoundFile cf = new CompoundFile(data,
                data.getPosition(),
                outputStream,
                readCompoundFile);
        cf.write();

        outputStream.flush();
        data.close();

        if (cs) {
            outputStream.close();
        }

        // Cleanup the memory a bit
        data = null;

        if (!workbookSettings.getGCDisabled()) {
            System.gc();
        }
    }

    /**
     * Adds the biff record data to the memory allocated for this File
     *
     * @exception IOException
     * @param record the record to add to the excel data
     */
    public void write(ByteData record) throws IOException {
        byte[] bytes = record.getBytes();

        data.write(bytes);
    }

    /**
     * Gets the current position within the file
     *
     * @return the current position
     */
    int getPos() throws IOException {
        return data.getPosition();
    }

    /**
     * Used to manually alter the contents of the written out data.  This
     * is used when cross-referencing cell records
     *
     * @param pos the position to alter
     * @param newdata the data to modify
     */
    void setData(byte[] newdata, int pos) throws IOException {
        data.setData(newdata, pos);
    }

    /**
     * Sets a new output file.  This allows the same workbook to be
     * written to various different output files without having to
     * read in any templates again
     *
     * @param os the output stream
     */
    public void setOutputFile(OutputStream os) throws IOException {
        if (data != null) {
            logger.warn("Rewriting a workbook with non-empty data");
        }

        outputStream = os;
        createDataOutput();
    }
}
